The present invention relates to an arrangement for the structure of a chair having a central pillar carrying a seat provided with a back support, and coacting with a base structure including at least three feet consisting of supporting members integral with, and projecting transversely from, a central sleeve accommodating the pillar, the free end portions of the members projecting a given distance from the sleeve and having fastening elements for wheels or floor-contacting member by which the chair contacts a floor or other substructure.
There is usually a problem with this kind of chair, particularly when the back support is provided with a neck rest, in which there is a greatly increased risk of the chair tipping over if the standard base structure is used.